Method and apparatus for producing apertured nonwoven fabric



March '19, 1963 H. w. GRISWOLD ETAL 3,081,500

METHOD AND APPARATUS FOR PRODUCING APERTURED NONWOVEN FABRIC 9Sheets-Sheet l Original Filed April 26, 1955 March 19, 1963 H. w.GRISWOLD ET AL 3,081,500

METHOD AND APPARATUS FOR PRODUCING APERTURED NONWOVEN FABRIC OriginalFiled April 26, 1955 9 Sheets-Sheet 2 ATTO/P/VfYS March 19, 1963 H. w.GRISWOLD ETAL 3,081,500

METHOD AND APPARATUS FOR PRODUCING APERTURED NONWOVEN FABRIC OriginalFiled April 26, 1955 9 Sheets-Sheet 3 March 19, 1963 H. w. GRISWOLD ETAL3,081,500

METHOD AND APPARATUS FOR PRODUCING APERTURED NONWOVEN FABRIC 1 FiledApril 26, 1955 9 Sheets-Sheet 5 Origina March 19, 1963 H. w. GRXSWOLDETAL 3,081,500

METHOD AND APPARATUS FOR PRODUCING APERTURED NONWOVEN FABRIC OriginalFiled April .26, 1955 9 Sheets-Sheet 6 March 19, 1963 H. w. GRISWOLDETAL METHOD AND APPARATUS FOR PRODUCING APERTUREDNONWOVEN FABRIC 9Sheets-Sheet 7 Original Filed April 26, 1955 INVENTORSI 1 a, W ISM/OLD$5025; 544:5 43 42 2; O 4 g a ATTORNEYS- March 19, 1963 H. w. GRISWOLDETAL 3,081,500

METHOD AND APPARATUS FOR PRODUCING APERTURED NONWOVEN FABRIC OriginalFiled April 26, 195 5 9 Sheets-Sheet 8 a? :T T Z8-G 7T i5 1s 15 I 1 I aa4 a4 xmww Q6 .35 9492 99 /02 98 /02 9 v .1 i INVENTORS.

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9 ATTORNEYS.

March 19, 1963 H. w. GRISWOLD ET AL 3,081,500

METHOD AND APPARATUS FOR PRODUCING APERTURED NONWOVEN FABRIC OriginalFiled April 26, 1955 9 Sheets-Sheet 9 T1E1.E.4 71:12. E. n n r n n 7k Ev 'a T 0 0 g Q o w C 705 lo 0 0 o 0 b 0 IIIl'III/II/II" v v"'IIIIIIIIIIIIIII 24 Q9 3 8 ATTORNEYS.

United States Patent 31 Claims. (Cl. 19-161) This invention relates totextile fabrics, as well as means and methods for producing them, and ismore particularly concerned with so-called nonwoven fabrics, i.e.,fabrics produced directly from fibers without the use of conventionalspinning, weaving, or knitting operations, and to the method andapparatus for making the same.

The present application is a division of our co-pending applicationSerial No. 503,872, filed April 26, 1955, which application was in turna continuation-in-part of our co-pending applications Serial Nos.437,037 (now abandoned) and 437,038, both filed June 16, 1954.

Heretofore, nonwoven fabrics have been essentially different instructure from fabrics which have been woven or knitted. In a woven orknitted fabric, the fibers of the material making up the fabric do notoccur individually, but are twisted into yarns or threads which in turnare woven or knitted into the fabric. In the well-known spinningoperation, fibers are spun or twisted together tightly into frictionaland inter-locking engagement with One another to form yarns which aresubstantially circular in cross section. It is these yarns, not thefibers acting individually, which serve as the structural members of theresulting woven or knitted fabrics. Generally speaking, these fabricscomprise reticular structures of intersecting, intertwining yarns whichdefine interstices between them.

Nonwoven fabrics have been of two main types, felts and bonded webs. Ineach of these, the fibers making up the fabric occur individually andact individually as structural members. This is true even though thefibers in many felts are so highly interlocked and compressed togetherthat it is difficult to identify individual fibers. Hat felts, forinstance, are extremely dense, relatively hard fabrics without apparentinterstices, which are quite dissimilar in appearance and qualities towoven or knitted structures. On the other hand, the fibers in bondedwebs are usually flatly assembled in layers, more or less oriented inone direction, as in a card web; or arranged in a random manner, as inan air laid isotropic web. Various bonding agents have been used toprint a binder pattern on such webs or to impregnate them to hold theindividual fibers together. In this type of tabric, the fibers mayremain relatively straight and overlapping one another with very littleinterlocking between them. They are usually arranged in a more or lessuniformly spaced condition in the plane of the web, in such a way thatonly very small randomly occuring interstices are apparent between theoverlapped fibers and those fibers between interstices remain spaced andmore or less fiatly arranged, possessing little similarity to the yarnsof woven or knitted fabrics.

The present invention contemplates a nonwoven fabric wherein the fibersare arranged to define a predetermined pattern of holes or openings withmost of the fiber segments bordering the holes extending in substantialparallelism with portions of their perimeters. In

general, the fibers are oriented in interconnected groupings or webareas extending between the holes in a predetermined patterncorresponding to the aforementioned I, 3,081,500 Patented Mar. 19, 1963pattern of holes. The resulting fabric may be made to resemble aparticular woven or knitted fabric. The groupings or groups areconnected by fibers extending 'from one to another in such a way thatthey are common to a plurality of groupings. It is preferred that theaverage length of the fibers be considerably greater than the lengths ofthe groups containing them with the result that the groups predominantlycomprise only parts or segments of fibers passing through them.Preferably the fibers average at least about 4 inch in length or overand are textile-like in nature, i.e., flexible and distinct or unbeatenin the case of wood pulp. In general, the groupings are connected atjunctures wherein the fibers extend in a plurality of diversedirections, while the fiber segments in the groups are relativelyparallelized with respect to one another and more closely assembled thanat the junctures. In one embodiment of a fabric according to thisinvention, the fiber segments in the groups are closely associated andsubstantially par-allelized along the axes of the groups to the extentthat the groups resemble spun yarns. The segments may be so closelyarranged in overlapping relationship about the axes of the groups thatthe groups possess yarn-like thickness and are generally yarn-like incross section.

In the foraminous structure formed by the interconnected fiber groupingsthe fibers lie in a state of mechanical equilibrium. The fibers aremechanically engaged, both frictionally and/or by interlocking of thefibers, to the extent that the arrangement of fibers is one of equi-Generally speaking, the frictional engagement and interlocking betweenthe fibers in the groupings, while contributing strength to the fabric,may be insuificient in itself to provide adequate tensile strength formany applications. Therefore, it may be desirable to strengthen thefabric in some way. For instance, an adhesive bonding material or bindermay be applied by means such as printing or impregnation. As will bedescribed more fully hereinafter, a binder may be contained in the webor layer of fibers from which the fabric is produced during and afterits transformation into the fabric of this invention. However, even thisbinder may not be present in sufiicien-t quantity and addi tional bindermay be required to provide adequate strength.

Due to their structure and appearance and other qualities described inthe foregoing paragraph, fabrics of this invention are particularlyadapted for use in surgical dressings, absorbent dressings such assanitary napkins and diapers, most suit-ably for covering sanitarynapkins and diapers, in wiping cloths, toweling, filter materials,

lining materials, industrial base fabrics, as a substitute for gauze andgauze-like fabrics in general, and a variety of other applications.

The present invention contemplates methods for producing the fabric ofthis invention from a base web or layer of fibers such as may beproduced by carding, garnetting, air deposition, papermaking techniques,etc. These methods involve the application of external forces to such aWeb to move its fibers into groupings in fiber accumulating zonesarranged in a predetermined pattern. Means comprising spaced projectionsdefining interconnected grooves or spaces between them arranged in apredetermined pattern, may be employed for this purpose. External forcesmay be applied to the web to move the fibers it contains into thegrooves or spaces between the projections. For instance, the web may beplaced between molding means defining spaced projections and acooperating resilient surface which may be oscillated slightly withrespect to one another in the direction of the lay of the web to movethe fibers away from the ends of the projections and into the spacesbetween them. The resilient surface may be presented by one side of asponge rubber belt which first may constrain the fibers of the web incontact with the ends of the projections and then move them relative tothe projections into the aforesaid spaces. The shape, size, andarrangement of the projections and correspondingly the shape, size, andarrangement of the openings in the resulting fabric and the arrangementof the fiber groupings between them may be varied to provide fabrics ofdifferent patterns resembling various woven and knitted and otherfabrics such as gauze, buckram, marquisette, lace, etc.

Advantages of the invention other than those generally described abovewill be apparent from the following description and claims takentogether with the drawings wherein:

FIG. 1 is a photomicrograph of a typical nonwoven fabric according toone embodiment of this invention at an original enlargement ofapproximately 6 to 1;

FIG. 2 is a photomicrograph of a portion of the fabric of FIG. 1 at anoriginal enlargement of about 30 to 1;

FIG. 3 is a photomicrograph of a similar fabric according to thisinvention at an original enlargement of about 24 to 1;

FIG. 4 is a schematic plan view of a typical base web from which thefabric of this invention may be produced;

FIG. 5 is an enlarged cross sectional view taken along the line 5-5 ofFIG. 4;

FIG. 6 is a schematic plan view of the web of FIG. 4 after it has beenrearranged to produce a fabric typical of one embodiment of thisinvention;

FIG. 7 is an enlarged sectional view taken along the line 7-7 of FIG. 6;

FIG. 8 is a photomicrograph of a somewhat different fabric according tothis invention at an original enlargement of about 14 to 1;

FIG. 9 is a photomicrograph of still another fabric at an originalenlargement of approximately 30 to 1;

FIG. 10 is a view in elevation of a device for producing a fabricaccording to this invention;

FIG. 11 is a view partly in section and partly in elevation along theline 11-11 of FIG. 10;

FIG. 12 is a plan view of the surface of the rearranging means of thedevice of FIG. 10;

FIG. 13 is an enlarged sectional view along the line 1313 of FIG. 12;

FIG. 14 is an enlarged plan view of molding means comprising taperedprojections;

FIG. 15 is a sectional view along the line 1515 of FIG. 14;

FIG. 16 is a view similar to FIG. 14 of molding means comprisinghexagonal projections with inclined sides;

FIG. 17 is a similar view showing molding means comprising roundprojections arranged in a square pattern;

FIG. 18 is a plan view of means comprising triangular projections;

FIG. 19 is a plan view of means presenting spaced frustro-conicalprojections;

FIG. 20 is an enlarged schematic sectional view along the line 20-20 ofFIG. 19 showing a layer of starting material positioned between the endsof the projections and cooperating means also in section;

FIG. 21 is a view similar to FIG. 20 at a later stage in the process;

FIG. 22 is a plan view similar to FIG. 19 showing a somewhat differentform of projections;

FIG. 23 is a sectional view similar to FIG. 20 along the line 23-23 ofFIG. 22;

FIG. 24 is a plan View of a woven screen rearranging means according tothis invention;

FIG. 25 is a view partly in section and partly in elevation along theline 2525 of FIG. 24;

FIG. 26 is a plan view of means comprising specially shaped projectionsarranged in a lace-like pattern.

FIG. 27 is a plan view of a fabric produced employing the means of FIG.26; and

FIG. 28 is a schematic view partly in longitudinal section of anotherdevice for producing a fabric according to this invention.

Referring to FIGS. 1, 2, and 3 of the drawings, there are shown typicalportions of nonwoven fabrics according to one embodiment of thisinvention comprising interconnected yarn-like groupings or groups 21 ofclosely associated and substantially parallelized fiber segments. Thegroups are arranged in a definite pattern forming a gauze-like reticularstructure wherein interconnected groups extend at substantially anddegrees to one another. The fibers are quite closely associated in thegroups with the result that the groups appear tight and adjacent groupsdefine relatively distinct and square holes or openings 22 between them.The groups extending in the vertical direction in FIGS. 2 and 3 appearheavier and more tightly formed, probably because the fibers in the basewebs from which these fabrics were produced were oriented predominantlyin this direction. There appear to be a number of fiber segments 23which lie outside the groupings and extend between them and some ofthese segments 23 may combine to form irregularly-located small groups24 extending between the main groups 21. As shown more particularly inFIGS. 2 and 3, the groups 21 come together at junctures 26 where theyare interconnected by fibers 25 which are common to more than one of thegroups. The fibers passing through the junctures 26 are oriented in aplurality of diverse directions forming diamond shaped fiber areas whichappear similar to highway intersections. Since it is difficult todistinguish the shape and arrangement of the individual fibers in FIGS.1, 2, and 3, a more detailed description of this type of fabric will bereserved for the somewhat stylized version of FIGS. 6 and 7, describedhereinafter.

Referring to FIGS. 4 and 5, a nonwoven fabric according to oneembodiment of this invention may be produced from a base web of flexiblefibers 28 arranged in substantially nonoriented, overlapping,intersecting relation with one another, such that there is only slightentanglement between them. The fibers in the web are flatly assembled innongrouped relationship with one another, such that they define onlyrelatively small interstices 29 between them. The web may contain asmall percentage of a uniformly dispersed moisture softenable adhesivebinder to assist in maintaining the web integrity as it is subjected toforces designed to cause its fibers to be rearranged into a fabricaccording to this invention.

In FIGS. 6 and 7, there is shown a fabric of this invention producedfrom the above-described base web, wherein the fibers 28 are bent andarranged in a gauzelike reticular structure of interconnected groupings31 of fiber segments. The groups 31 extend at approximately 90 and 180degrees to one another and, except where there is an irregularity in thefabric, as at 32 in FIG. 6, four groups come together at each juncture33 wherein the fibers are oriented in a plurality of diverse directions.Some fibers from each of these four groups pass into each of the othergroups at the juncture with the result that the groups are connected byfibers common to a plurality of groups. The individual fibers may beconsiderably longer than the groups containing them with the result thateach fiber may extend through a plurality of interconnected groups andeach of the groups may contain only a portion or a segment 30 of each ofthe fibers passing through it. The fiber segments may be closelyassociated and substantially parallelized about the longitudinal axes ofthe groups to the extent that the segments in the groups appear to be insubstantial contact with one another along their length when viewed bythe naked eye or under a microscope at low magnifications. Theindividual fibers may pass from one group and enter a given junctureinto any one of the other three groups entering the same juncture. Thus,they may either extend substantially straight or take 90 degree turnsinto the groups interconnected at these angles. Although the bends inthe fibers may be due to their presence in groups interconnectedatIright angles to one another, the fibers curve as they bend to passfrom one group to another. The tighter the groups are formed, thesharper will be the bends in the fibers and the shorter will be theirradii of curvature. The fibers may extend through a more or lesssymmetrical set of groups in such a way that they will be sinuous inshape. However, the fibers may wander throughout the groups turning backon themselves and adopting irregular configurations. .The paths oftypical individual fibers 28 are shown in heavy lines in FIG. 6. 1

The resulting groups 31 of fiber segments 30 may possess yarn-likethickness. The fiber segments may be substantially parallelized andclosely arranged about the longitudinal axes of the groups to the extentthat the groups are yarn-like in cross section. As shown in FIG. 7, thegroups 31 possess yarn-like thicknesses in two dimensions, both in theplane of the web and perpendicular thereto, and tend to be oval in crosssection. The fibers in a given cross section of the fabric of thisinvention may appear closely assembled in the groups 31, in such a waythat there appears to be a good deal of contact between them. The spacedgroups define enlarged holes 34 between themselves similar to theinterstices between the yarns of a conventional woven gauze. Most of thefiber segments bordering the holes extend in substantial parallelismwith corresponding portions of their perimeters. That is to say, theyextend around the holes and do not present ends adjacent theirperimeters. In general, the tighter the groups are formed, the moreclearly defined will be the voids between them. The size of the holes 34will depend to a large extent upon the means employed to produce thefabric of this invention, as will be described hereinafter. As mentionedhereinbefore in connection with FIGS. 1, 2, and 3, there may be acertain percentage of fiber segments which will fail to enter the maingroups and will extend between them as random segments 35 or relativelysmall random bundles 36. However, in general the openings 34 may bedescribed as being substantially free of fibers.

Referring to FIGS. 8 and 9 of the drawings, there are shown porousnonwoven fabrics comp-rising fibers 37 arranged in interconnected fibergroupings or web areas 38 defining holes or openings 39 arranged inpredetermined patterns in the fabric. The holes 39 are distinct andsubstantially free of fibers passing through them. However, a certainnumber of random fiber segments 50 may remain extending through theopenings without detracting materially from the porosity of the fabricor the clarity of hole formation. Most of the fibers or fiber segmentsbordering the holes extend in substantial parallelismwith portions ofthe perimeters of the holes. That is to say, they extend around theholes and do not present ends adjacent their perimeters. As shown moreparticularly in FIG. 9, the holes may be bordered by smaller groups 60of fiber segments wherein the fibers are more closely assembled than inthe remaining areas of. the fabric between holes. However, the fiberarrangement across the areas 38 between holes may be substantiallyuniform in density as appears to be the case in many areas of FIG. 8.

The fiber groupings or areas 38 between holes may contain a multiplicityof much smaller interconnected groups 73 of fiber segments, as shown toan extent in FIG. 9. In FIG. 9, it appears that a large percentage ofthe fibers in the areas between holes 39 have lost their identity asindividual fibers and merged with other fibers forming a network ofinterconnected groups or strands 73 of highly parallelized fibersegments. As illustrated, particulanly in FIG. 8, the main fibergroupings 38 may be interconnected at junctures 74 wherein the fibersextend in a .pluraltiy of diverse directions. The fibers in thegroupings 38 extending between the junctures 74 in FIG. 8 are moreparallelized and appear more closely assembled than at the junctures.However, they are not as closely assembled and parallelized as the fibersegments in the groupings 21 of FIGS. 1, 2, and 3. Most of the fibers inFIGS. 8 and 9 are considerably longer than the greatest dimension of theholes which they define with the result that they may extend around orpass several holes extending in different directions from grouping togrouping. Thus, the fibers may be shaped or bent to conform to thereticular structure in which they lie.

In the fabric of this invention, the fibers are in mechanical engagementwith one another to the extent that the fabric structure is inmechanical equilibrium. The fibers are in frictional engagement with oneanother and their bent or curled configurations are entangled orinterlocked and resist separation, In general, the firctional engagementand interlocking between the fibers is greater when they lie ininterconnected yarn-like groups of fiber segments. In other words, bothfrictional engagement and interlocking are a function of the tightnessor loose ness of the fiber groupings. The closeness of the segmentstends to constrain the fibers in the groups and the bends in the fiberstend to prevent their movement along the axes of the groups. Obviously,the longer the fibers, the more segments there will be in frictionalengagement and the more bends or curls will. be entangled. Thus, fabricstrength is a function of fiber length as well as other variables. -If abinder is present in the base web, a certain amount of it may becomeeffective to a certain extent to hold the fibers in their new positionsin the groupings. The effective binder may assist in holding the fibersin close contact with one another and may concentrate within the groupsthemselves, to assist in holding them together.

As mentioned hereinbefore, the starting material for the nonwoven fabricof this invention may be a layer of fibers 28 arranged in overlappingintersecting relation with one another, such that there is only slightentanglement between them, as shown in FIGS. 4 and 5. Webs of this typemay be formed by carding, by air deposition, by liquid deposition suchas in a paper making process, etc. They may be formed in a single layeror by laminating a plurality of webs formed by these techniques. Thefibers in the base web may be arranged in a random manner or more orless oriented, as in a card web, or a card web laminate. The individualfibers may be relatively straight or slightly bent, occurringindependently in the Web in nongnouped intersecting relation with oneanother. They may intersect at various angles to one another such that,generally speaking, adjacent fibers only come into contact at the pointswhere they cross. The overlapping, intersecting fibers form interstices29 between them which vary in size with the fiber density of the websuch that for preferred Web Weights of from to 600 grains per squareyard, only very small interstices are apparent. Webs ranging in Weightfrom below 100 grains per square yard to the neighborhood of 2,000grains per square yard may be rearranged into the fabric of this invention. Such webs may be held together by virtue of the mechanicalengagement, i.e., the frictional contact and the aforementioned slightentanglement, between its fibers, as well as :by any binder which may bepresent. Generally speaking, the fibers lie in mechanical equilibrium inthe web or layer.

A Web or layer of fibers, such as described above, may be subjected toexternal forces applied in a predetermined pattern. The patternedapplication of forces will cause portions of the fibers in the layer tomove from corresponding areas thereof into fiber accumulating zonessurrounding these areas. The newly positioned fibers are in a new stateof balanced equilibrium and will define holes or openings in the fabricarranged in accordance with the aforementioned pattern, as seen forexample in FIG. 6. In the movement of the fibers into closer proximitywith one another to produce a fabric as shown in FIG. 6, the externalrearranging forces applied to the fibers will ordinarily include lateraltranslatory components acting parallel to the plane of the web and othercooperating components of force causing individual fibers to move, withrespect to other fibers in the layer with which they overlap and arefrictionally engaged, into mechanical equilibrium in the most extremelateral position into which they are moved, as shown in FIG. 6, by therearranging forces.

During the application of external forces, sufficient local support mustbe provided for preventing these forces from destroying the webintegrity, i.e., from pulling the layer apart or from converting it intomere groups of fibers, etc The supporting means employed must allow thefibers to move during the application of these forces to the extent thatthey may assume positions in mechanical equilibrium in the fabric. Thefibers may be said to be in mechanical equilibrium in the fabric whenthe frictional engagement and interlocking between them hold themtogether.

An adhesive binder may be included in the web before its rearrangementinto a fabric according to this invention to provide local support andto facilitate web handling. However, such a binder may not be necessary,particularly when the web is fully supported by external means. A bindermay be included in the web during its formation, in the case of awet-formed web, for instance, or it may be added by impregnation,spraying, or other such means. In order that the fibers in the web mayenter into the fabric structure, they must be free to move to a certainextent locally with respect to one another, as described hereinbefore.This means that the binder should be rendered sufficiently soft orplastic during the application of these forces, to allow this movement.A solvent or softening agent such as water may be added to the web forthis purpose when the web contains a binder which may be softened inthis way.

It is preferred that some liquid, such as water, be uniformlydistributed in the web to assist in parallelizing fiber segments andbringing them into close association in the groups. The web may be wetto contain a maximum of water, for instance, prior to the application ofbundling forces, although in general, less water, in the neighborhood of50 to 250 percent moisture, is preferred. The term percent moistureabove, and when used in the following specification and claims, refersto percentage of moisture by weight of the dry web. Most fibers willabsorb moisture, swell, and soften to a certain extent while retainingthis moisture, such that if moistened fibers are brought together, theywill tend to conform and fit closely with one another. As the fibersswell and soften under the influence of moisture, they may becomenonresiliently bendable to the extent that they may be bent or curled toconform to the grooves and will retain their new configurations incontact with the other fibers. It is believed that the surface tensioneflect of the moisture in the grooves tends to move the fiber segmentsin the grooves closer togther and into parallelism in the groups. Oncethe fibers are brought into alignment, the surface tension of themoisture tends to hold them there. The intensity of this effect willdepend upon the amount of liquid present in the web. While good resultsmay be obtained in accordance with the methods of this invention whenthe web contains 50 percent moisture, for instance, the above-mentionedsurface tension effect should be greater with higher moisture contents.

'In FIGS. 10 through 13, there is shown an illustra tive device forproducing a fabric according to this invention. A fibrous Web, notshown, of the type described above, may be placed between a groovedmolding member 40 and a resilient block 41 which are adapted to beoscillated with respect to one another along their plane of contact tocause the fibers in the web to move into the grooves of the moldingmember and form a fabric of predetermined pattern according to thisinvention. The

surface of the molding member 40 presents a pattern of closely spacedintersecting grooves 42. As shown in FIGS. 12 and 13, the grooves orfiber accumulating zones intersect at right angles to one another andare spaced equally in the longitudinal and transverse directions of themolding member such that they define square raised portions orprojections 43 between them. Since the fiber rearranging forcesresulting from relative movement of grooved molding member '40 andresilient block 41 are applied only to the tops of raised portions 43,fiber accumulating zones 42 between the raised portions aresubstantially free of all translatory and other applied forces. Thegrooves 42 may be substantially square in section and spaced from oneanother by an amount approximately equal to their width with the resultthat a sectional view through the molding member has a square toothedappearance. The molding member 40 may be of any suitable material whichis sufficiently strong and will resist the wear and corrosion incidentto its use. Polymethylmethacrylate, hard rubber, corrosion resistantmetals and other similar materials will give good results. The resilientblock 41 may comprise any suitable resilient material such as spongerubber, for example.

As shown in FIGS. 10 and 11, the molding member 40 is supported by anopen frame 44 comprising a pair of transverse bars 45 connecting theends of a pair of spaced longitudinal bars 46. The longitudinal bars arefixed to a suitable support, such as a table 47, and the mold 40 isresiliently secured to the transverse bars 45 which are separated by adistance slightly greater than the length of the mold 40. The moldingmember is attached to a layer of resilient material 48, such as wovenmetal screening, which in turn may be extended and secured at its endsto the transverse bars 45. Those portions 49 of the resilient layer 48between the ends of the molding member 40 and the transverse bars 45 arefree to flex slightly to provide resilient support for the mold. Theresilient block is similarly supported in an inverted fashion by asimilar open frame. The resilient block 41 is attached to a resilientscreen 51 which is secured to a frame 52 comprising longitudinal bars 53and transverse bars 54 joined to form a structure corresponding to thatof the aforementioned frame 44 supporting the molding block 40.

In order to oscillate the resilient block 41 and the molding member 40with respect to one another to cause the fibers to move into the groovesof the mold, eyes 55 and 56 are provided on one end and one side,respectively, of the upper frame 52, extending outwardly therefrom. Oneof the eyes 56 is secured directly to the side of the frame and theother is secured to the frame through a block 57 which is attached tothe upper surface of one of the end bars 54, thereby placing the twoeyes on the same level. Fittings 58 containing recesses 59 verticallyaligned with the normal position of the eyes are fixed to the table 47outside of the lower frame 44. Levers 61 and 62, such as steel bars, formoving the upper frame with respect to the lower frame may be insertedthrough the eyes with their lower ends seated in the aforementionedrecesses 59. oscillatory motion is imparted in the longitudinaldirection by grasping the upper end of the end lever 61 and moving itback and forth steadily in a longitudinal direction, and transverseoscillation may be achieved by operating the side lever 62 transverselyin the same manner. The fibers of the web may be pushed into the groovesof molding member 40 by the relative motion of members 40 and 41produced by such oscillation and the resulting lateral translatorycomponents of force acting parallel to the plane of the web. Inaddition, they may be rolled into closer contact by the rotationalcomponents of force applied, through the relative motion of members 40and 41, to the fibers confined between the oscillatory members. Theserotational components of force will help to cause individual fibers tomove with respect to other fibers in 9. the web with which they overlapand are frictionally engaged. In addition, the vibrational components offorce caused by vibration of the moving parts of the apparatus shown inFIGS. through 13, which may include vertical components, will alsoassist in producing the aforesaid fiber motion.

Clamping means are provided in order to hold the resilient block 41firmly upon the grooved surface of the molding member 40. These meanscomprise a resilient pressure distributing block 6'4 which may be of thesame material as the first resilient block, a clamping plate 65 forpressing downwardly upon the upper surface of the pressure distributingblock, and releasable clamping means attached to the clamping plate '65and the table 47 for holding or clamping the plate in position withrespect to the table. The pressure distributing block 64 rests withinthe upper frame 52 upon the wire screen 51 supporting the resilientblock, while the clamping plate 65 presses down upon the upper surfaceof the block with the clamping means extending from the plate to thetable on either side of the upper and lower frame. The clamping meanscomprises pairs of spaced T-shaped members 66 attached to opposite sidesof the clamping plate and corresponding pairs of spaced angle feet 67secured to the table 47 on opposite sides of the lower frame 44.Corresponding legs 68 and '69 of the T-shaped members 66* and theclamping feet 67 extend downwardly and upwardly, respectively, towardseach other on either side of the molding unit. Co-acting parts ofluggage-type clamps 71 are attached to these legs to clamp the plate 65to the table 47. The clamps 71 are located adjacent opposite ends of themolding member 40 in order to assure that pressure exerted upon theresilient block 41 through the above described clamping means will bedistributed fairly uniformly over the mating surfaces of the moldingmember and the resilient block 41.

The resilient block 41 may be oscillated alternately lengthwise andcrosswise by alternate operation of the end and side levers 61 and 62,or it may be oscillated in only one direction by the use of theappropriate lever. Alternate operation is advantageous since it aidseffective grouping and the production of more uniform groups. Thebenefits of alternate operation may be attained to some extent byswinging the end lever 61, for instance, back and forth in a circularpath to oscillate the block 41 alternately lengthwise and crosswise in acircular path. Portions or segments of a certain percentage of thefibers in the starting web may not move into the grooves 42 of themolding member and may extend across the raised portions 43 of themolding surface between the fiber groupings lying in the grooves. Morethan one of such random segments may come together to form a smallrandom group extending between the main groups. The alternate operationtends to minimize the occurrence of such random segments or groups. Forexample, when the raised portions 43 are approximately inch wide,oscillation of the upper frame 52 in a circular path having a diameterof approximately inch at approximately 180 cycles per minute forrelatively short periods of time, say in the order of about 10 secondsor even less, will provide a fabric according to this invention. Since asubstantial portion of the oscillatory motion of the frame 52 will beabsorbed by the flexure of the resilient material in the block 41, it isdifiicult to determine the exact amplitude of oscillation of the surfaceof the resilient block 41 in contact with the web in the above example.It is preferred that the amplitude of oscillation of this surface atleast be equal to the individual widths of the raised portions '43 inorder to push the fibers overlying these portions into the grooves 42.

FIGS. 14 through 18 illustrate various groove patterns or patterns ofprojections for the molding member which will produce openings and causefiber groupings to be produced in corresponding patterns in the fabricof this invention. The square pattern of FIGS. 12 and 13 may 10 bemodified somewhat, as shown in FIGS. 14 and 15 which illustrateprojections 81 with square ends 82 hav ing inclined side surfaces 83defining grooves 84 between them. The tapered projections 81 facilitatethe removal of the fabric from the molding member as well as aiding inits production. FIG. 16 illustrates the use of hexagonal projections 85to define grooves 86 arranged in a reticular pattern wherein threegrooves interconnect at 120 degrees to one another. A molding surface ofthis type will cause a similar arrangement of interconnected fibergroupings. The hexagonal raised portions may be tapered for the reasonsmentioned above in connection with FIG. 14. FIG. 17 illustrates "amolding surface having cylindrical projections 87 while FIG. 18illustrates projections 88 which are triangular. The triangularprojections of FIG. 18 are arranged in such a way as to define a patternof grooves '89 wherein six grooves interconnect and extend at '60degrees to one another.

Referring to FIGS. 19 through 21, there is illustrated a method andmeans for producing a fabric according to this invention. A base web orfibrous layer of the type described hereinbefore may be placed in anopen position between hole defining means 92 below the web and webengaging means 93 above it, which are adapted to oscillate to a limitedextent with respect to one another in the plane of the web for producinga porous nonwoven fabric. The hole defining means 92 may comprise amultiplicity of spaced projections 94 arranged in a definite pattern ona member presenting a continuous surface 95 between projections. Theprojections 94 may be in the form of small nobs, conical frustums orsimilar protuberances, preferably having side surfaces '96 which areinclined toward the continuous surface 95 of the hole defining member92. The projections may be arranged in a pattern corresponding to thepattern of holes desired to be produced in the resulting fabric. Asshown in FIG. 19, the projections may be uniformly spaced and arrangedin a square pattern. The web engaging member 93 preferably comprises aresilient surface such as that presented by one side of a sponge rubberbelt.

As shown schematically in FIG. 20, the web may be placed between thehole defining member 92 and the web engaging member 93 and the membersmay be brought together to support the web between the ends of theprojections 94 and the inner surface of the web engaging member 93.Preferably, the web is supported under pressure at least to the extentthat the ends of the projections 94 and the surface of the web engagingmember 93 would be in contact were it not for the web between them. Themembers then may be oscillated slightly with respect to one another suchthat the motion of the Web engaging member 93 with respect to theprojections 94 will cause those portions of the fibers originallypassing over the projections to move away from the ends of theprojections. As shown in FIG. 21, the projections 94 then may contactthe surface of the web engaging member 93, and the web 91 may besupported by the inclined sides 96 of the projections and the surface 95of the hole defining member 92. Preferably, the Web engaging memberpresents a surface which is relatively rough compared with the surfacesof the projections since it is desirable that the web enter into greaterfrictional contact with this member as compared to the projections sothat the web will tend to move more with the surface of the ,Webengaging member 93 than with the ends of the projections 94 during theaforesaid oscillation.

The motion of the web 91 relative to the ends of the projections 94tends to bend and rearrange those portions of the fibers passing overthe projections in new positions in mechanical equilibrium adjacent theedges of the projections, thereby producing holes in the Web in the wayof the projections. As described hereinbefore, the rearranged fibersretain their new configurations, frictionally engaged and interlockedwith proximate fibers to define relatively distinct and permanent poresor holes in the fabric. The size and shape of the holes produced willdepend to a large extent upon the size and shape of the projections 94,although the holes may be elongated in the direction of orientation ofthe fibers in the base web, as shown in FIG. 9.

It is preferred that the web engaging member 93 be of resilient materialso that it will fit over the ends of the projections 94 and protrudeslightly into the spaces between them when the web engaging member 93and the hole defining member 92 are brought together as aforesaid. Whenthe members are oscillated with respect to one another while holding theweb with this sort of resilient interfitting between them, the fibersegments in the way of the projections 94 will be moved away from theends of the projections and urged into the spaces or fiber accumulatingzones between them by the protruding portions 97 of the resilient member93. The resilient web engaging member also may move the fiber segmentsdownwardly along the inclined sides 96 of the projections to produceholes larger than otherwise would be produced if a resilient member isnot employed. A fabric may be produced by relative oscillation of themembers 92 and 93 in one direction, or in different directions in theplane of the web.

As shown in FIGURES 22 and 23, projections 98 may be closely spaced anddesigned with shallow inclined sides 99 to give relatively tight groupformation with relatively short projections. The short inclinedprojections 98 will slowly work their way into the web and theprotruding portions of a cooperating resilient member 101 may beemployed to move fibers away from the ends of the projections 98 anddown their sides until relatively tight groups 102 of fibers are formedin the fiber accumulating zones around the bases of the projections.

Another type of hole defining member is illustrated in FIGS. 24 and 25wherein a screen of interwoven wires is employed to define the patternof holes desired. This screen may be woven with the wires 104 in onedirection remaining relatively straight while the wires 105 in the otherdirection are crimped. A pattern of spaced projections is formed bythose portions 106 of the crimped wires 105 which form alternateintersections with the relatively noncrirnped wires 1104. Theseprojections are relatively blunt and oblong and have sides inclined inthe direction of the crimped wires, with the result that they tend toproduce slightly oblong holes when oscillated with respect to aresilient Web engaging surface. Those portions of the crimped 'wires 105between projections cooperate with the noncrimped wires 104 tosubstitute for the continuous surface 95 of FIGS. 19 through 21 toprovide means for supporting the web after penetration by theprojections.

Still another form of hole defining member 108, which may be used in thesame manner as the hole defining members illustrated in FIGURES 13-25,is shown schematically in FIGURE 26. The member 108 comprises spacedirregularly shaped projections 109. These projections are shaped andarranged in a pattern resembling the holes in a lace. In FIGURE 27 thereis illustrated a lacy nonwoven fabric, produced on the member 108, whichcomprises holes 111 shaped and arranged to correspond to the projections109. This fabric comprises closely assembled fibers arranged ininterconnected groups 112 of fiber segments. The groups 112 define theholes 111 between them.

As shown in FIG. 28, the hole defining or fabric producing member andthe fabric engaging member may be in the form of continuous moving belts114 and 115, respectively, in which case they may be urged together witha web 116 between them and oscillated with respect to one another bymeans contacting their opposite surfaces as they move along. Assuggested previously, the fabric engaging belt 115 may be of spongerubber or a similar resilient material which will resist the continuouswear and flexure it must withstand. The hole defining member theoscillating rollers.

may comprise a hard rubber or any other suitable hard material, when inthe form illustrated in FIGS. 14 through 23, or it may comprise arelatively flexible sheet of matcrial with inserts of relatively hardmaterial forming the projections. The screening of FIGS. 24 and 25 alsomay be in the form of a continuous belt.

The belts 1'14 and with the web 116 between them may be passed betweensets of upper rollers 117 and lower rollers 118 designed to beoscillated axially, .or axially and circumferentially, with respect toone another in a manner such as described in U.S. Patent No. 2,093,709or 2,506,855, both disclosing machines, and mechanisms for machines ofthe continuous felting type. As explained in U.S. Patent No. 2,093,709(page 4, column 2, lines 3-5), the rollers are subjected to acircumferential vibration which is superposed upon the movement ofrotation. Thus a given point on the surface of a roller continues toadvance generally because of the rollers rotation even though at anyparticular moment it may be moving backwards within a narrow angulardistance because of the circumferential vibration or oscillatorymovement of the roller. The resilient belt 115 may pass around the upperrollers 117 and guide rollers 121 at the front and the rear of the upperrollers, and the hole defining belt 114 may pass around the lowerrollers 118 and guide rollers 122 at the front and the rear thereof. Theupper and lower guide rollers may be spaced to cause the upper and lowerbelts to converge as they move toward the oscillating rollers anddiverge as they leave these rollers.

The Web 116 may enter between the belts 114 and 115 where they convergeat the front of the oscillating rollers and leave them where theydiverge at the rear of these rollers. Suitable tables 123 and 124 may beprovided for supporting the web 116 adjacent the points where it entersand leaves the belts. The rollers 117 and 118 may oscillate axially orcircumferentially relattve to one another while they continue to rotateto feed the superimposed belts 114 and 115 between them at an economicalproduction rate. The upper and lower sets of rollers may be spaced orurged together in such a way as to press the resilient belt and the webagainst the ends of the projections on the lower belt. The relativeoscillatory movement of the rollers may be transmitted through the belts114 and 115 to their adjacent or contrguous surfaces. As will be seenfrom consideration of FIG. 28, this relative movement will apply to thefibers lateral translatory components of force acting parallel to theplane of the web, rotational components of force, and vibrationalcomponents of force. All these will act to cause individual fibers tomove with respect to the other fibers in the layer so that therearranged fiber segments will remain in mechanical equilibrium.

The upper rollers alone may be oscillated in which case their movementwill be distributed and partially absorbed by the resilient material ofthe web engaging belt 115 in contact therewith. Thus, the amplitude ofoscillation of the inner surface 125 of the resilient belt 115 may beconsiderably less than the corresponding amplitudes of As mentionedhereinbefore, the relative oscillatory motion of the belts may occur inonly one direction, however, oscillation in different directions in theplane of the web may be desirable from the standpoint of uniformity. Theamplitudes of relative motion between the inner surface 125 of the webengaging belt and the ends of the projections on the hole producing beltshould be controlled to prevent damage to the web in the form ofexcessively large holes or tears, clumps of loose fibers, etc.

It will be seen that in the embodiments of FIGS. 10 through 28, the webengaging belt 115 (and the similar element illustrated in the otherfigures) applies agitating forces to the web as a whole. These forcesare applied generally throughout the entire fibrous layer. The fiberrearranging forces which operate on the layer result from theinteraction between these agitating forces and the more specific forcesapplied by the spaced projections of the aperture defining belt (such asthe projections shown in FIGS. 14 to 23) in opposition to thegeneralized agitating forces.

It is only by the action of some type of opposed forces that a group offibers can be rearranged into consolidated and parallelized groups ofsegments. Important though the agitating forces are, they cannotaccomplish anything by themselves; nor, indeed, could the spacedprojections acting alone. The interaction of the two elements is theessential thing, and that interaction takes place at laterally andlongitudinally spaced areas of the web, resulting in the application offiber rearranging forces at those areas.

When the screening of FIGS. 24 and 25 is employed, an additionalresilient belt, not shown, may be employed between the screening and thelower oscillating rollers 118. This additional belt tends to decreasethe relative movement between the hole defining projections 106 of thescreening and the inner surface 125 of the upper belt and also acts todistribute the oscillatory forces and cushion the impact of these forcesupon the screening. However, satisfactory results may be achieved withthe screening without the additional resilient belt described above. Forinstance, good results have been obtained with a web of the typedescribed hereinbefore interposed between a resilient belt of spongerubber /8 inch thick and a hole defining belt of 24 x 20 wire screeningof the type generally described above, when the resilient belt andscreening are run between upper and lower rollers about 4 inches indiameter at a linear speed of approximately 20 feet per minute while theupper rollers oscillate inch both axially and circumferentially atfrequencies ranging between 800 and 1,600 cycles per minute. At suchspeeds a nonwoven fabric according to this invention may be producedduring the period the web is in contact with the screening which may bein the neighborhood of l to seconds, depending upon the number ofrollers employed and the inclination of the resilient belt to thescreening.

The base web or layer of starting material may comprise natural fibers,such as fibers of cotton, wood, wool, jute, ramie, or abaca; orartificial fibers of viscose ray-on, cuprammonium rayon, celluloseacetate, nylon, Dynel or other materials, alone or in combination withone another. Viscose rayon is known to give excellent results inproducing a fabric according to this invention. While relatively longtextile-type fibers above normal papermaking lengths and close to normaltextile length or over, say of about A" to 2" or longer are preferredfor textile applications, shorter fibers, below 4 inch in length, withinthe paper range, may be used for these and other applications. It ispreferred that the shorter papermaking fibers, if used, be unbeaten orsubstantially unhydrated if a textile-like fabric is desired. In thisconnection, shorter fibers of woodpulp, for instance, may be mixed withlonger fibers with the result that the longer fibers will enhance thestrength of the resulting fabric and the shorter fibers will decreaseits cost. Fiber length is also an important factor affecting fabricstrength, as described hereinbefore, and fiber lengths and materialsshould be chosen with this and other fabric characteristics in mind.

There are a number of suitable adhesive bonding materials, or binderswhich may be included in the web prior to, or during, rearrangement. Forinstance, water softenable materials including the following may beused: beaten cellulose jellies of woodpulp, caroa, ramie, etc.; naturalgums including k'araya, locust bean, gum arabic and others; starches;and synthetics such as polyvinyl alcohol, carboxymethylcellulose,polyvinyl acetate, etc. Suitable binders, softenable by solvents otherthan water, are exemplified by polyvinyl chloride and polyvinyl butyraland their copolymers, while nonreversible binders which 14 may be usedif rearrangement occurs before they are set, include urea-formaldehydeand melamine-formaldehyde.

Having now described the invention in specific detail and exemplifiedthe manner in which it may be carried into practice, it will be readilyapparent to those skilled in the art that innumerable variations,applications, modifications and extensions of the basic principlesinvolved may be made without departing from its spirit or scope. Thusthe fabrics of the present invention may be laminated with otherfabrics, with paper or with other materials, or employed in a host ofways that willbe readily apparent to the skilled artisan.

We claim:

1. The method of producing a nonwoven fabric having spaced holesarranged in a predetermined pattern from a layer of irregularly arrangedfibers, which comprises sup porting the layer locally to maintain itsintegrity, by means including spaced projections arranged in accordancewith said pattern, subjecting the supported layer at laterally andlongitudinally spaced areas corresponding to said predetermined patternto adjacent, simultaneously applied fiber rearranging forces, saidforces moving segments of said fibers from local areas of the layercorresponding to said predetermined pattern into closer proximity and ininterlocking and frictional engagement with one another, said layerbeing supported with suflicient freedom to allow said segments to bemoved as aforesaid into mechanical equilibrium in their new positions,whereby a fabric is produced comprising distinct openings arrangedsubstantially in accordance with said pattern.

2. The method of producing a nonwoven fabric having spaced holesarranged in a predetermined pattern from a layer of irregularly arrangedfibers, which comprises constraining the layer into contact with theends of projections arranged in a predetermined pattern havinginterconnected spaces between them, and maintaining said constraintwhile imparting movement to the entire layer relative to saidprojections and substantially in the plane of the layer to move fibersit contains away from the ends of the projections and into the spacesbetween them.

3. The method of producing a nonwoven fabric having space-d holesarranged in a predetermined pattern from a layer of irregularly arrangedfibers, which comprises constraining the layer into contact with theends of projections arranged in a predetermined pattern havinginterconnected spaces between them, and maintaining said constraintwhile imparting substantially oscillatory movement to the entire layerrelative to said projections and predominantly in the plane of the layerto move fibers it contains away from the ends of the projections andinto the spaces between them.

4. The method of producing a nonwoven fabric having spaced holesarranged in a predetermined pattern from a layer of irregularly arrangedfibers which comprises supporting the layer between means comprisingprojections arranged in a predetermined pattern on one side of saidlayer and cooperating means on the other side of the layer, saidprojections having interconnected spaces between them, iand moving saidcooperating means and said projections relative to one another in theplane of said layer to move fiber segments away from the ends of theprojections and into the spaces between them and into closer proximityand in interlocking and frictional engagement with one another whereby afabric is produced comprising distinct openings arranged substantiallyin accordance with said pattern.

5. The method of producing a nonwoven fabric having spaced holesarranged in a predetermined pattern from a layer of irregularly arrangedfibers which comprises supporting the layer between means comprisingprojections arranged in a predetermined pattern on one side of saidlayer and resilient means on the other side of the layer, saidprojections having interconnected spaces between them, and moving saidresilient means relative to said projections in the plane of said layerto move fiber segments away from the ends of the projections and intothe spaces between them and into closer proximity and in interlockingand frictional engagement with one another, whereby a fabric is producedcomprising distinct openings arranged substantially in accordance withsaid pattern.

6. The method of producing a nonwoven fabric having spaced holesarranged in a predetermined pattern from a layer of irregularly arrangedfibers, which comprises constraining the layer into contact with theends of projections arranged in a predetermined pattern by means of aresilient member on the opposite side of said layer to said projections,said projections having interconnected spaces between them, andmaintaining said constraint while imparting movement to the entire layersubstantially in the plane of the layer and relative to the ends of saidprojections by moving said resilient member with respect to saidprojections to push fiber segments forming said layer into the spacesbetween said projections.

7. The method of producing a nonwoven fabric having spaced holesarranged in a predetermined pattern from a layer of irregularly arrangedfibers, which comprises constraining the layer into contact with theends of projections arranged in a predetermined pat-tern by means of aresilient member on the opposite side of said layer to said projections,said projections having interconnected spaces between them, andmaintaining said constraint while imparting movement to the entire layersubstantially in the plane of the layer and relative to the ends of saidprojections by moving said resilient member with respect to saidprojections, said resilient member protruding slightly into the spacesbetween the projections to facilitate movement of fibers into saidspaces.

8. The method of producing a nonwoven fabric having spaced holesarranged in a predetermined pattern from a layer of irregularly arrangedfibers which comprises constraining the layer into contact with the endsof spaced projections defining interconnected grooves between themarranged in a predetermined pattern, and maintaining said constraintwhile imparting movement to the entire layer relative to saidprojections and substantially in the plane of the layer to move fibersit contains away from the ends of the projections and into the groovesbetween them.

9. The method of producing a nonwoven fabric having spaced holesarranged in a predetermined pattern from a layer of irregularly arrangedfibers, which comprises wetting the layer, constraining said layer intocontact with the ends of projections arnanged in a predetermined patternhaving interconnected spaces between them, and maintaining saidconstraint while imparting movement to the entire layer relative to saidprojections and substantially in the plane of the layer to move fibersit contains away from the ends of the projections and into the spacesbetween them.

10. The method of producing a nonwoven fabric having spaced holesarranged in a predetermined pattern from a layer of irregularly arrangedfibers, said layer including a liquid softenable adhesive binderdistributed substantially uniformly therein, which comprises wetting thelayer to soften said binder, constraining said layer into contact withthe ends of projections arranged in a predetermined pattern havinginterconnected spaces between them, and maintaining said constraintwhile imparting movement to the entire layer relative to saidprojections and substantially in the plane of the 'layer to move fibersit contains away from the ends of the projections and into the spacesbetween them.

11. A mechanism for producing a nonwoven fabric having spaced holesarranged in a predetermined regular pattern from a nonwoven fibrouslayer having an irregular pattern, said mechanism comprisinghole-defining means comprising projections arranged in a predeterminedpattern having interconnected spaces between them, layerengaging meansadapted to cooperate with said hole-defining means for continuouslyconfining the layer between them in contact with the ends of saidprojections, means for constraining said hole-defining means and saidlayerengaging means together for confining the layer as aforesaid, andmeans for moving said hole-defining means and said layer-engaging meanswith respect to one another substantially in the plane of the layerbetween them, whereby the fibers in the layer will be moved away fromthe ends of said projections to produce a fabric having perforationsarranged in substantially the same pattern as are the ends of saidprojections.

12. A mechanism for producing a nonwoven fabric having spaced holesarranged in a predetermined regular pattern from a nonwoven fibrouslayer having an irregular pattern, said mechanism comprisinghole-defining means comprising projections arranged in a predeterminedpattern having interconnected spaces between them, layerengaging meanspresenting a resilient surface adapted to cooperate with saidhole-defining means for continuously confining the layer between them incontact with the ends of said projections, means for constraining saidholedefining means and said layer-engaging means together for confiningthe layer as aforesaid, and means for moving said hole-defining meansand said layer-engaging means with respect to one another substantiallyin the plane of the layer between them, whereby the fibers in the layerwill be moved away from the ends of said projections to produce a fabrichaving perforations arranged in substantially the same pattern as arethe ends of said projections.

13. A mechanism for producing a nonwoven fabric having spaced holesarranged in a predetermined regular pattern from a nonwoven fibrouslayer having an irregular pattern, said mechanism comprisinghole-defining means comprising projections arranged in a predeterminedpattern having interconnected spaces between them, layerengaging meansadapted to cooperate with said holedefining means for continuouslyconfining the layer between them in contact with the ends of saidprojections, means for constraining said hole-defining means and saidlayer-engaging means together for confining the layer as aforesaid, andmeans for imparting oscillatory relative movement to said hole-definingmeans and said layerengaging means substantially in the plane of thelayer between them, whereby the fibers in the layer will be moved awayfrom the ends of said projections to produce a fabric havingperforations arranged in substantially the same pattern as are the endsof said projections.

14. Apparatus for producing a nonwoven fabric having spaced holesarranged in a predetermined pattern from a layer of irregularly arrangedfibers which comprises means for engaging said layer throughout the areato be affected, the surface of said engaging means having indentedportions forming interconnected spaces arranged in a predeterminedpattern corresponding to the desired predetermined pattern of the fabricto be produced, fiber rearranging means having a surface generallycomplementary to the unindented portions of the surface of said engagingmeans, means for pressing the engaging means and fiber rearranging meanstogether with the fibrous starting layer therebetween, and means forproducing relative movement between the engaging means and fiberrearranging means in at least one direction measured in the plane of thestarting layer to force the fibers into said patterned spaces andarrange them into interconnected groups of fiber segments in saiddesired predetermined pattern, said groups being interconnected byfibers common to a plurality of groups, wherein some of the segments ineach of said groups are substantially parallel to and consolidated withother segments in the group, wherein substantial segments of individualinterconnecting fibers are mechanically engaged with other fibersegments in various groups extending in more than one direction measuredin the plane of the fabric, and wherein the fibers in said fabric lie inmechanical engagement with i one another and in mechanical equilibrium.

15. A mechanism for producing a nonwoven fabric having spaced holesarranged in a predetermined regular pattern from a nonwoven fibrouslayer having an irregular pattern, said mechanism comprising ahole-defining belt having projections arranged in a predeterminedpattern having interconnected spaces between them, a layer-engaging beltadapted to cooperate with said holedefining belt for supporting thelayer between them in contact with the ends of said projections, rollersspaced to allow said belts and said layer to be passed between them insuperimposed relationship, said rollers being spaced to constrain saidbelts together and being adapted for relative oscillatory movement,whereby said rollers may be oscillated with respect to one another toimpart relative oscillatory movement to the projections on thehole-defining belt and the corresponding inner surface of the layerengaging belt.

16. The method of producing a nonwoven fabric having spaced holesarranged in a predetermined pattern from a layer of irregularlyarranged, overlapping fibers in frictional engagement with one another,said fibers being capable of movement in response to applied rearrangingforces, which comprises supporting the layer locally throughout the areato be affected to maintain its integrity; while the layer is sosupported subjecting the same to fiber rearranging forces comprisingforces having translatory components of force acting parallel to theplane of the layer and other cooperating components of force selectedfrom the group consisting of rotational components,vibrational'components, and both rotational and vibnational components,said fiber rearranging forces being applied to fibers of the layer atlaterally and longitudinall-y spaced areas corresponding to saidpredetermined pattern, adjacent translatory components of saidrearranging forces being applied simultaneously in opposed directions tofiber groups lying between the respective areas of application of saidcomponents, to move segments of' fibers in said layer sideways from theareas to whichsaid rearranging forces are applied into closer proximityto and increased parallelism with segments of adjacent fibers lyingbetween said areas; at the same time moving individual fiber segments,by application of said translatory and cooperating components of force,with respect to other fibers in the layer with which they overlap andare 'frictionally engaged so as to bring any segment of said individualfibers so moved into mechanical equi- -librium in the most extremelateral position into which it is moved by said fiber rearrangingforces; and grouping the aforesaid fiber segments in fiber accumulatingzones arranged in an interconnected pattern substantially coming spacedholes arranged in a predetermined pattern from a layer of irregularlyarranged, overlapping fibers in frictional engagement with one another,said fibers being capable of movement in response to applied rearrangingforces, which comprises supporting the layer locally throughout the areato be affected to maintain its integrity; while the layer is sosupported subjecting the same to fiber rearranging forces comprisingforces having translatory components of force acting parallel to theplane of the layer and other cooperating components of force selectedfrom the group consisting of rotational components, vibrationalcomponents, and both rotational and vibrational components, said fiberrearranging forces being applied to fibers of the layer at laterally andlongitudinally spaced areas corresponding to said predetermined pattern,adjacent translatory components of said rearranging forces being appliedsimultaneously in opposed directions to fiber groups lying between therespective areas of application of said components, to move segments offibers in said layer sideways fr-om the areas to which said rearrangingforces are applied into closer proximity to and increased parallelismWith segments of adjacent fibers lying between said areas; at the sametime moving individual fiber segments, by application of saidtranslatory and cooperating components of force, with respect to otherfibers in the layer with which they overlap and are frictionally engagedso as to bring any segment of said individual fibers so moved intomechanical equilibrium in the most extreme lateral position into whichit is moved by said fiber rearranging forces; and grouping the aforesaidfiber segments in quiescent fiber accumulating zones arranged in aninterconnected pattern substantially complementary to said predeterminedpattern of holes, said zones being substantially free of any resultantforces acting upon the fibers accumulated therein.

=18. The method of producing a nonwoven fabric having spaced holesarranged in a predetermined pattern from a layer of irregularlyarranged, overlappingfibers in frictional engagement with one another,said fibers being capable of movement in response to applied rearrangingforces, which comprises supporting the layer 10- cally throughout thearea to be affected to maintain its integrity; while the layer is sosupported subjecting the same to mechanical rearranging forcescomprising forces having translatory components of force acting parallelto the plane of the layer and other cooperating components of forceselected from the group consisting of rotational components, vibrationalcomponents, and both rotational and vibrational components, said fiberrearranging forces being applied to fibers of the layer at laterally andlongitudinally spaced areas corresponding to said predetermined pattern,adjacent translatory components of said rearranging forces being appliedsimultaneously in opposed directions to fiber groups lying between therespective areas of application of said components, to move segments offibers in said layer sideways from the areas to which said rearrangingforces are applied into closer proximity to and increased parallelismwith segments of adjacent fibers lying between said areas; at the sametime moving individual fiber segments, by application of saidtranslatory and cooperating components of force, with respect to otherfibers in the layer with which they overlap and are frictionallyengagedso as to bring any segment of said individual fibers so movedinto mechanical equilibrium in the most extreme lateral position intowhich it is moved by said fiber rearranging forces; and grouping theaforesaid fiber segments in fiber accumulating Zones arranged in aninterconnected pattern substantially complementary to said predeterminedpattern of holes, said zones being substantially free of any translatoryforces acting parallel to the plane of the fibrous layer.

19. The method of producing a nonwoven fabric having spaced holesarranged in a predetermined pattern from a layer of irregularlyarranged, overlapping fibers in frictional engagement with one another,saidfibers being capable of movement in response to applied rearrangingforces, Which comprises supporting the layer 10- cally throughout thearea to be affected to maintain its integrity; while the layer is sosupported subjecting the same to fiber rearranging forces comprisingforces having translatory components of force acting parallel to theplane of the layer and other cooperating components of force selectedfrom the group consisting of rotational components, vibrationalcomponents, and both rotational and vibrational components, said fiberrearranging forces being applied to fibers of the layer at laterally andlongitudinally spaced areas corresponding to said predetermined pattern,to move segments of fibers in said layer sideways from the areas towhich said rearranging forces are applied into closer proximity to andincreased parallelism 19 with segments of adjacent fibers lying betweensaid areas; at the same time moving individual fiber segments, byapplication of said translatory and cooperating components of force,with respect to other fibers in the layer with which they overlap andare frictionally engaged so as to bring any segment of said individualfibers so moved into mechanical equilibrium in the most extreme lateralposition into which it is moved by said fiber rearranging forces; andgrouping the aforesaid fiber segments in fiber accumulating zonesarranged in an interconnected pattern substantially complementary tosaid predetermined pattern of holes, said zones being substantially freeof any resultant translatory forces acting parallel to the plane of thefibrous layer.

20. The method of producing a nonwoven fabric having spaced holesarranged in a predetermined pattern from a layer of irregularlyarranged, overlapping fibers in frictional engagement with one another,said fibers being capable of movement in response to applied rearrangingforces, which comprises supporting the layer locally throughout the areato be affected to maintain its integrity; while the layer is sosupported moving segments of fibers in said layer sideways from areas ofthe layer spaced laterally and longitudinally from each other intocloser proximity to and increased parallelism with segments of adjacentfibers lying between said spaced areas by applying to the fibersexternal rearranging forces comprising forces having lateral translatorycomponents of force acting parallel to the plane of the layer and othercooperating components of force selected from the group consisting ofrotational components, vibrational components, and both rotational andvibrational components; at the same time moving individual fibersegments, by application of said translatory and cooperating componentsof force, with respect to other fibers in the layer with which theyoverlap and are frictionally engaged so as to bring any segment of saidindividual fibers so moved into mechanical equilibrium in the mostextreme lateral position into which it is moved by said fiberrearranging forces; and grouping the aforesaid fiber segments in fiberaccumulating zones arranged in an interconnected pattern substantiallycomplementary to said predetermined pattern of holes, said zones beingsubstantially free of any result-ant translatory forces acting parallelto the plane of the fibrous layer.

21. The method of producing a nonwoven fabric having spaced holesarranged in a predetermined pattern from a layer of irregularlyarranged, overlapping fibers in frictional engagement with one another,said fibers being capable of movement in response to applied rearrangingforces, which comprises supporting the layer locally throughout the areato be affected to maintain its in tegrity; while the layer is sosupported moving segments of fibers in said layer sideways from areas ofthe layer spaced laterally and longitudinally from each other intocloser proximity to and increased parallelism with segments of adjacentfibers lying between said spaced areas by applying to the fibersmechanical rearranging forces comprising forces having lateraltranslatory components of force acting parallel to the plane of thelayer and other cooperating components of force selected from the groupconsisting of rotational components, vibrational compo nents, and bothrotational and vibrational components; at the same time movingindividual fiber segments, by application of said translatory andcooperating components of force, with respect to other fibers in thelayer with which they overlap and are frictionally engaged so as tobring any segment of said individual fibers so moved into mechanicalequilibrium in the most extreme lateral position into which it is movedby' said fiber rearranging forces; and grouping the aforesaid fibersegments in fiber accumulating zones arranged in an interconnectedpattern substantially complementary to said predetermined pattern ofholes, said zones being substantially free of any translatory forcesacting parallel to the plane of the fibrous layer.

22. The method of producing a nonwoven fabric having spaced holesarranged in a predetermined pattern from a wetted layer of irregularlyarranged, overlapping fibers in frictional engagement with one another,said fibers being capable of movement in response to applied rearrangingforces, which comprises supporting the wetted layer locally throughoutthe area to be affected to maintain its integrity; while the layer is sosupported moving segments of fibers in said layer sideways from areas ofthe layer spaced laterally and longitudinally from each other intocloser proximity to and increased parallelism with segments of adjacentfibers lying between said spaced areas by applying to the fibersexternal rearranging forces comprising forces having lateral translatorycomponents of force acting parallel to the plane of the layer and othercooperating components of force selected from the group consisting ofrotational components, vibrational components, and both rotational andvibrational components; at the same time moving individual fibersegments, by application of said translatory and cooperating componentsof force, with respect to other fibers in the layer with which theyoverlap and are frictionally engaged so as to bring any segment of saidindividual fibers so moved into mechanical equilibrium in the mostextreme lateral position into which it is moved by said fiberrearranging forces; and grouping the aforesaid fiber segments in fiberaccumulating zones arranged in an interconnected pattern substantiallycomplementary to said predetermined pattern of holes, said zones beingsubstantially free of any resultant translatory forces acting parallelto the plane of the fibrous layer.

23. The method of producing a nonwoven fabric having spaced holesarranged in a predetermined pattern from a wetted layer of irregularlyarranged, overlapping fibers in frictional engagement with one another,said fibers being capable of movement in response to applied rearrangingforces, which comprises supporting the wetted layer locally throughoutthe area to be affected to maintain its integrity; while the layer is sosupported moving segments of fibers in said layer sideways from areas ofthe layer spaced laterally and longitudinally from each other intocloser proximity to and increased parallelism with segments of adjacentfibers lying between said spaced areas by applying to the fibersmechanical rearranging forces comprising forces having lateraltranslatory components of force acting parallel to the plane of thelayer and other cooperating components of force selected from the groupconsisting of rotational components, vibrational components, and bothrotational and vibrational components; at the same time movingindividual fiber segments, by application of said translatory andcooperating components of force, with respect to other fibers in thelayer with which they overlap and are frictionally engaged so as tobring any segment of said individual fibers so moved into mechanicalequilibrium in the most extreme lateral position into which it is movedby said fiber rearranging forces; and grouping the aforesaid fibersegments in fiber accumulating zones arranged in an interconnectedpattern substantially complementary to said predetermined pattern ofholes, said zones being substantially free of any translatory forcesacting parallel to the plane of the fibrous layer.

24. The method of producing a nonwoven fabric having spaced holesarranged in a predetermined pattern from a wetted layer of irregularlyarranged, overlapping fibers in frictional engagement with one another,said fibers being capable of movement in response to applied rearrangingforces, which comprises supporting the wetted layer locally throughoutthe area to be affected to maintain its integrity; while the layer is sosupported subjecting the same to fiber rearranging forces comprisingforces having translatory components of force acting parallel to theplane of the layer and cooperating components of force selected from thegroup consisting of rotational components, vibrational components, andboth rotational and vibrational components, said fiber rearrangingforces being applied to fibers of the layer at laterally andlongitudinally spaced areas corresponding to said predetermined pattern,to move segments of fibers in said layer sideways from the areas towhich said rearranging forces are applied into closer proximity to andincreased parallelism with segments of adjacent fibers lying betweensaid areas; at the same time moving individual fiber segments, byapplication of said translatory and cooperating components of force,with respect to other fibers in the layer with which they overlap andare frictionally engaged so as to bring any segment of said individualfibers so moved into mechanical equilibrium in the most extreme lateralposition into which it is moved by said fiber rearranging forces; andgrouping the aforesaid fiber segments in fiber accumulating zonesarranged in an interconnected pattern substantially complementary tosaid predetermined pattern of holes, said zones being substantially freeof any resultant translatory forces acting parallel to the plane of thefibrous layer.

25. The method of producing a nonwoven fabric having spaced holesarranged in a predetermined pattern from a wetted layer of irregularlyarranged, overlapping fibers in frictional engagement with one another,said fibers being capable of movement in response to applied rearrangingforces, which comprises supporting the wetted layer locally throughoutthe area to be affected to maintain its integrity; while the layer is sosupported subjecting the same to fiber rearranging forces comprisingforces having translatory components of force acting parallel to theplane of the layer and other cooperating components of force selectedfrom the group consisting of rotationalcomponents, vibrationalcomponents and both rotational and vibrational components, said fiberrearranging forces being applied .to fibers of "the" layer at laterallyand longitudinally spaced areas corresponding to said predeterminedpattern, adjacent translatory components of said rearranging forcesbeing applied simultaneously in opposed directions to fiber groups lyingbetween the respective areas of application of said components, to movesegments of fibers in said layer sideways from the areas to which saidrearranging forces are applied into closer proximity to and increasedparallelism with segments of adjacent fibers lying between said areas;at the same time moving individual fiber segments, by application ofsaid translatory and cooperating components of force, with respect toother fibers in the layer with which they overlap and are frictionallyengaged so as to bring any segment of said individual fibers so movedinto mechanical equilibrium in the most extreme lateral position intowhich it is moved by said fiber rearranging forces; and grouping theaforesaid fiber segments in fiber accumulating zones arranged in aninterconnected pattern substantially complementary to said predeterminedpattern of holes, said zones being substantially free of any resultanttranslatory forces acting parallel to the plane of the fibrous layer.

26. The method of producting a nonwoven fabric having spaced holesarranged in a predetermined pattern from a wetted layer of irregularlyarranged, overlapping fibers in frictional engagement with one another,said fibers being capable of movement in response to applied rearrangingforces, which comprises supporting the wetted layer locally throughoutthe area to be affected to maintain its integrity; while the layer is sosupported subjecting the same to fiber rearranging forces comprisingforces having translatory components of force acting parallel to theplane of the layer and other cooperating components of force selectedfrom the group consisting of rotational components, vibrationalcomponents and both rotational and vibrational components, said fiberrearranging forces being applied to fibers of the layer at laterally andlongitudinally spaced areas corresponding to said predetermined pattern,adjacent translatory components of said rearranging forces being appliedsimultaneously in opposed directions to fiber groups-lying between therespective areas of application of said components, to move segments offibers in said layer sideways from the areas to which said rearrangingforces are applied into closer proximity to and increased parallelismwith segments of adjacent fibers lying between said areas; at the sametime moving individual fiber segements, by application of saidtranslatory and cooperating components of force, with'respect to otherfibers in the layer with which they overlay and are frictionally engagedso as to bring any segment of said individual fibers so moved intomechanical equilibrium in the most extreme lateral position into whichit is moved by said fiber rearranging forces; and grouping the aforesaidfiber segments in quiescent fiber accumulating zones arranged in aninterconnected pattern substantially complementary to said predeterminedpattern of holes; said zones being substantially free of any resultantforces acting upon the fibers accumulated therein.

27. The method of producing a nonwoven fabric having spaced holesarranged in a predetermined pattern from a wetted layer of irregularlyarranged, overlapping fibers in frictional engagement with one another,said fibers being capable of movement in response to applied rearrangingforces, which comprises supporting the wetted layer locally throughoutthe area to be affected to maintain its integrity; while the layer is sosupported subjecting the same to mechanical rearranging forcescomprising forces having translatory components of force acting parallelto the plane of the layer and other cooperating components of forceselected from the group consisting of rotational components, vibrationalcomponents and both rotational and vibrational components, said fiber rearranging forces being applied to fibers of the layer at laterally andlongitudinally spaced areas corresponding to said predetermined pattern,adjacent translatory components of said rearranging forces being appliedsimultaneously in opposed directions to fiber groups lying between therespective areas of application of said components, to move segments offibers in said layer sideways from the areas to which said rearrangingforces are applied into closer proximity to and increased parallelismwith segments of adjacent fibers lying between said areas; at the sametime moving individual fiber segments, by application of saidtranslatory and cooperating components of force, with respect to otherfibers in the layer with which they overlap and are frictionally engagedso as to bring any segment of said individual fibers so moved intomechanical equilibrium in the most extreme lateral position into whichit is moved by said fiber rearranging forces; and grouping the aforesaidfiber segments in fiber accumulating zones arranged in an interconnectedpattern substantially complementary to said predetermined pattern ofholes, said zones being substantially free of any translatory forcesacting parallel to the plane of the fibrous layer.

28. The method of producing a nonwoven fabric having spaced holesarranged in a predetermined pattern from a layer of irregularlyarranged, frictionally engaged fibers which comprises supporting saidlayer locally throughout the area to be affected to maintain itsintegrity, applying external agitating forces to substantially theentire area of said fibrous layer to move fibers it contains generallyin the plane of said layer, and constraining the resulting fibermovement at intervals spaced laterally and longitudinally across saidlayer in a predetermined pattern, whereby a fabric may be producedcomprising fibers rearranged into groups of fiber segments defining anarrangement of holes corresponding to said predetermined pattern ofconstraint.

29. The method of producing a nonwoven fabric having spaced holesarranged in a predetermined pattern

1. A METHOD OF PRODUCING A NONWOVEN FABRIC HAVING SPACED HOLES ARRANGEDIN A PREDETERMINED PATTERN FROM A LAYER OF IRREGULARLY ARRANGED FIBRES,WHICH COMPRISES SUPPORTING THE LAYER LOCALLY TO MAINTAIN ITS INTEGRITY,BY MEANS INCLUDING SPACED PROJECTIONS ARRANGED IN ACCORDANCE WITH SAIDPATTERN, SUBJECTING THE SUPPORTED LAYER AT LATERALLY AND LONGITUDINALSPACED AREAS CORRESPONDING TO SAID PREDETERMINED PATTERN TO ADJACENT,SIMULTANEOUSLY APPLIED FIBER REARRANGING FORCES, SAID FORCES MOVINGSEGMENTS OF SAID FIBERS FROM LOCAL AREAS OF THE LAYER CORRESPONDING TOSAID PREDETERMINED PATTERN TO CLOSER PROXIMITY AND IN INTERLOCKING ANDFRICTIONAL ENGAGEMENT WITH ONE ANOTHER, SAID LAYER BEING SUPPORTED WITHSUFFICIENT FREEDOM TO ALLOW SAID SEGMENTS TO BE MOVED AS AFORESAID INTOMECHANICAL EQUILIBRIUM IN THEIR NEW POSITIONS, WHEREBY A FABRIC ISPRODUCED COMPRISING DISTINCT OPENINGS ARRANGED SUBSTANTIALLY INACCORDANCE WITH SAID PATTERN,
 11. A MECHANISM FOR PRODUCING A NONWOVENFABRIC HAVING SPACED HOLES ARRANGED IN A PREDETERMINED REGULAR PATTERNFROM A NONWOVEN FIBROUS LAYER HAVING AN IRREGULAR PATTERN, SAIDMECHANISM COMPRISING HOLE-DEFINING MEANS COMPRISING PROJECTIONS ARRANGEDIN A PREDETERMINED PATTERN HAVING INTERCONNECTED SPACES BETWEEN THEM,LAYERENGAGING MEANS ADAPTED TO COOPERATE WITH SAID HOLE-DEFINING MEANSFOR CONTINUOUSLY CONFINING THE LAYER BETWEEN THEM IN CONTACT WITH THEENDS OF SAID PROJECTIONS, MEANS FOR CONSTRAINING SAID HOLE-DEFININGMEANS AND SAID LAYERENGAGING MEANS TOGETHER FOR CONFINING THE LAYER ASAFORESAID, AND MEANS FOR MOVING SAID HOLE-DEFINING MEANS AND SAIDLAYER-ENGAGING MEANS WITH RESPECT TO ONE ANOTHER SUBSTANTIALLY IN THEPLANE OF THE LAYER BETWEEN THEM, WHEREBY THE FIBERS IN THE LAYER WILL BEMOVED AWAY FROM THE ENDS OF SAID PROJECTIONS TO PRODUCE A FABRIC HAVINGPERFORATIONS ARRANGED IN SUBSTANTIALLY THE SAME PATTERN AS ARE THE ENDSOF SAID PROJECTIONS.